Synchrotron X-Ray Fluorescence Microscopy of Gallium in Bladder Tissue following Gallium Maltolate Administration during Urinary Tract Infection

Amouse model of cystitis caused by uropathogenic Escherichia coliwas used to study the distribution of gallium in bladder tis-sue following oral administration of galliummaltolate during urinary tract infection. The median concentration of gallium in homogenized bladder tissue from infected mice was 1.93g/g after daily administration of galliummaltolate for 5 days. Syn-chrotron X-ray fluorescence imaging and X-ray absorption spectroscopy of bladder sections confirmed that gallium arrived at the transitional epithelium, a potential site of uropathogenic E. coli infection. Gallium and iron were similarly but not identi-cally distributed in the tissues, suggesting that at least some distributionmechanisms are not common between the two ele-ments. The results of this study indicate that galliummaltolate may be a suitable candidate for further development as a novel antimicrobial therapy for urinary tract infections caused by uropathogenic E. coli. Urinary tract infections (UTIs) are common in humans anddogs, and most of these infections are caused by uropatho-genic strains of Escherichia coli (UPEC) (1, 2). In addition to pa-tient discomfort and economic burdens from treatment costs and lost work time, failure to cure these infections can lead to serious complications, including pyelonephritis and septicemia (3). An-timicrobial resistance in UPEC complicates therapy and is of con-cern for both canine and human patients because these pathogen